Abstract
Rather than just providing an unstructured adhesive surface for leukocytes, cytokine-activated endothelial cells assemble preexisting tetraspanin-enriched microdomains to form endothelial adhesive platforms (EAPs) and endothelial docking structures. In this issue of the Journal of Cell Biology, Barreiro et al. (Barreiro, O., M. Zamai, M. Yáñez-Mó, E. Tejera, P. López-Romero, P.N. Monk, E. Gratton, V.R. Caiolfa, and F. Sánchez-Madrid. 2008. J. Cell Biol. 183:527-542) show how the immunoglobulin superfamily adhesion molecules intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 form nanoclusters with the tetraspanins CD9 and CD151 in a physiologically relevant system. Furthermore, convincing biochemical data suggest that these structures are distinct from lipid rafts.